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US5817532A
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Ferroelectric thin film device and method for making the same
Assignee: DIGITAL MFS Ltd
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Filing: 1996-04-29
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Granted: 1998-10-06
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Expires: 2016-04-29
Abstract
Abstract There are disclosed a ferroelectric thin film device and a method for making the same. The ferroelectric thin film device includes a bottom electrode formed on a substrate, a ferroelectric thin film formed on the bottom electrode to contain a predetermined amount of Ta and have grains arranged in a regularly repeating pattern, and a top electrode formed on the ferroelectric thin film. The method for making a ferroelectric thin film includes the steps of forming a bottom electrode on a substrate, forming on the bottom electrode a Ta doped ferroelectric thin film, forming a top electrode on the ferroelectric thin film at regular intervals, and performing a rapid thermal annealing process on the ferroelectric thin film, using a radiant heating device, to induce crystallization.
Inventors
- 👤 Seungki Joo
- 👤 Jaehyun Joo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:15
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10N; H10N30/00; H10N30/01; H10N30/80; H10N30/85; H10N60/00; H10N60/01; H10N60/80; H10N60/85; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6329; H10P14/65; H10P14/6516; H10P14/6544; H10P14/69; H10P14/692; H10P14/6938; H10P14/69398
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
58 words
A method for fabricating a ferroelectric thin film device comprising the steps of: forming a bottom electrode on a substrate; forming a tantalum (Ta) doped ferroelectric thin film on the bottom electrode; forming a top electrode on the ferroelectric thin film at regular intervals; and thereafter performing a thermal process on the ferroelectric thin film to induce crystallization.
Claim 2
Independent Claim
58 words
A method for fabricating a ferroelectric thin film device comprising the steps of: forming a bottom electrode on a substrate; forming a tantalum (Ta) doped ferroelectric thin film on the bottom electrode; forming a top electrode on the ferroelectric thin film at regular intervals; and thereafter performing a thermal process on the ferroelectric thin film to induce crystallization.
Claim 3
Dependent Claim
26 words
A method according to claim 1, wherein Ta added to the ferroelectric thin film has a content in the range of 0.5 atomic% to 4.0 atomic%.
Claim 4
Dependent Claim
18 words
A method according to claim 1, wherein said substrate is formed by forming insulating layer onto a substrate.
Claim 5
Dependent Claim
18 words
A method according to claim 1, wherein said top and bottom electrodes are formed by depositing Platinum (Pt).
Claim 6
Dependent Claim
25 words
A method according to claim 1, wherein said ferroelectric thin film is formed by performing a sputtering process forming a lead zirconate titanate thin film.
Claim 7
Dependent Claim
36 words
A method according to claim 1, wherein said top electrode is a Pt top electrode formed to have a size of 10 μm×10 μm at intervals of 50 μm on the lead zirconate titanate thin film.
Claim 8
Independent Claim
65 words
A method for fabricating a ferroelectric thin film device comprising the steps of: forming a bottom electrode on a substrate; depositing a seed material on an area of the bottom electrode at intervals by a photolithographic technique; forming a Ta doped ferroelectric thin film on the exposed bottom electrode and seed material; and performing a thermal process on the ferroelectric thin film to induce crystallization.
Claim 9
Independent Claim
65 words
A method for fabricating a ferroelectric thin film device comprising the steps of: forming a bottom electrode on a substrate; depositing a seed material on an area of the bottom electrode at intervals by a photolithographic technique; forming a Ta doped ferroelectric thin film on the exposed bottom electrode and seed material; and performing a thermal process on the ferroelectric thin film to induce crystallization.
Claim 10
Dependent Claim
41 words
A method according to claim 7, wherein the step of performing a thermal process in the ferroelectric thin film is carried out after the step of forming a Ta doped ferroelectric thin film on the exposed bottom electrode and seed material.
Claim 11
Independent Claim
77 words
A method for fabricating a lead zirconate titanate thin film device comprising the steps of: forming a bottom electrode of Pt on a substrate made of silicon dioxide (SiO 2 ) and silicon (Si); depositing a Ta-doped lead zirconate titanate thin film on said Pt bottom electrode; depositing a top electrode of Pt on said Ta-doped lead zirconate titanate thin film at regular intervals; and thereafter performing a thermal process on the lead zirconate titanate thin film.
Claim 12
Independent Claim
77 words
A method for fabricating a lead zirconate titanate thin film device comprising the steps of: forming a bottom electrode of Pt on a substrate made of silicon dioxide (SiO 2 ) and silicon (Si); depositing a Ta-doped lead zirconate titanate thin film on said Pt bottom electrode; depositing a top electrode of Pt on said Ta-doped lead zirconate titanate thin film at regular intervals; and thereafter performing a thermal process on the lead zirconate titanate thin film.
References Cited (Backward Citations)
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